Plans for an extension and the process

Hi. Normally we have plans showing the layout etc but you should also have calculations for sizing beams and depending on the type of roof construction would normally have a lot of details on joist size, specs of fire boarding, insulation required for thermal conductivity, drainage layout new and existing. But all this depends on what kind of extension and roof construction is required by the client not to mention the existing property type I:e mordern, period, listed etc. You would also need your local BCO (Building control officer) on board as they are the people who Inspect the work At different stages making sure the build is up to the current specs and regulations they will also need to see plans and calculations before he signs any work off as complete. Hope this all helps you if you need further guidance or a free quote please feel free to contact us direct. Kind regards Mark MJWD property maintenance and solutions.

It sounds as though you have the drawings for the purposes of planning permission but in order to be able to provide a quote builders will need to see Building Regs drawings (preferable having been approved by building control already). These have specification and detail for the build. Builders will also calculations and drawings for any structural steel work.

You are not alone. i often get people asking me to quote jobs from plan drawings that include no structural engineers calculations or in depth detail. As a builder all we can do is cover ourselves by pricing for a worst case scenario. I think you need to contact the architect and ask him for the structural engineers calculations as these will be needed further along the process. if its only a basic small extension then the plans don't really need a roof drawing just a spec on timber sizes.